PINES (Bemidji State University)
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Changes in Walleye Fecundity and Egg Size Before, During, and After Rehabilitation of the Red Lakes Fishery
No full textThe Red Lakes in northern Minnesota experienced a major Walleye Sander vitreus fishery crash in the late 20th century, but has since recovered to record abundances and supports a major commercial and recreational fishery. Fecundity is an integral aspect of recruitment that can contribute greatly to the understanding of fishery population dynamics. To elucidate the effects of varying Walleye densities and exploitation rates on fecundity and egg size in years 1989 (overexploited fishery), 2004 (recovering fishery), and 2017 (recovered fishery), we analyzed linear models that related fecundity or egg size to morphological features for these three sampling periods. Walleyes were collected spring 2004 (n=30) and 2017 (n=30) in the Tamarac River. Fecundity data from 1989 were provided by Bushong (1990). Fecundity was higher in 2004 and 1989 than in 2017. Egg size was significantly greater in 2017 than in 1989. Considerable distinctions in Walleye size at spawn existed between all sampling years. Variance in fecundity as well as egg and fish size between fishery status scenarios is likely attributable to varying exploitation rates and related Walleye densities; these two factors were shown to be good predictor variables. Models incorporating fishery status were developed and for certain management applications, these models could provide a higher degree of selectivity and estimation accuracy for fishery managers
Goldeye Hidon alosoides calorimetry in Red Lake
No full textGoldeye Hiodon alosoides are found across North America and are a relatively unstudied group of fish as they have had no economic value in the past. Ecologically speaking, these fish could have importance to the waters that they inhabit, as they are prey to fishes like Walleyes Sander vitreus, Northern Pike Esox lucius, and Muskellunge Esox masquinongy. These fish could potentially be vital to predatory fishes because of the amount of oil found in these fish, creating gram for gram more energy than compared to other consumable substances. The average energy density for all Goldeye was 6.73 kJ/g (SD = 1.11)
Spatial and Temporal Variability in Post-Larval Yellow Perch Density
No full textYellow Perch Perca flavescens are important as forage for other species and for sport fishing in many northern lakes. However, estimating post-larval Yellow Perch populations can be difficult because of many environmental factors that cause unexplained variation. The objective of this study was to help reduce unexplained variation by determining a post-larval Yellow Perch population density estimate on Blackduck Lake, MN, provide guidance to help determine the number of trawls required for trawling-based recruitment indices to achieve varying levels of precision, and test for the effects of wind speed and direction on post-larval Yellow Perch spatial variability. This study estimated a density of 0.45 fish/m\u27 (0.58 SD) during the sampling period (26 Jun - 07 Jul 2017). It was determined that between 10-15 trawls produced a precise density estimate; however, trawls should be taken over multiple days in varying wind speeds to avoid over/under estimation. Trawling should also be performed in-line with wind direction to ensure non-bias estimates are calculated from both upwind and downwind sectors. This study determined wind speed and direction had a significant influence on the distribution of post-larval Yellow Perch, as more fish were caught in the downwind sector until winds reached 15 kmph. At 15 kmph, fish densities were equal in the upwind and downwind sectors of the lake. Wind did not have a significant influence though on how post-larval Yellow Perch were distributed by total length. During high wind events, more fish were found in the upwind sector of the lake, suggesting that post-larval fish are being moved laterally out of non-towable areas. From the results of this study it appears Yellow Perch must continually relocate back into shallow areas after each high wind event moves them out of the non-trawlable areas, until they are strong enough to resist the wind
Does Anyone Trust the Government Anymore? Or Does It Depend on Who You Ask and When You Ask Them?
No full textPolitical scientists have been curious about trust and its impact on government for years. They have learned that governments who have earned the trust of their citizens are more effective in serving the people and are generally able to accomplish more. However, do levels of trust in government depend upon a person’s party affiliation and the party in power? Does partisan trust also vary depending on gender, race, education, or income level? I analyze data from the American National Election Survey (ANES) over time and conclude levels of trust in government rise and fall as power in government shifts back and forth between the two major parties. I also find interesting variations to trust levels when I look at the different demographics of the respondents. My research shows levels of partisan trust move up and down depending on which party controls the government. Further, there is not a significant level of change in trust for a 14 year period. This suggests the attention focused on the increasing polarization of society and how it affects our view of government may be overstated
Does Students United Really Help State Funding for Higher Education: Analyzing the Strength of State Student Associations Effect on State Higher Education Funding in the U.S. (2013-2018)
No full textThere are many different types of state student associations (SSAs). They simply work as a form of student systems. These organizations seek to represent their respective public college or university while also being a voice for state students. SSAs also lobby on big issues such as higher education funding at the state level. I evaluate the overall success of SSA types and higher education funding in the United States between 2013 and 2018. In order to test competing higher education funding theories and my thesis I used Phillip H. Pollock III’s states data (Pollock III, 2016) and Grapevine data from Illinois State University. I also used data from the Student Empowerment Training Project, which documents state student association types in each U.S. State. I researched the effect these state student associations or SSA types have on higher education funding across all 50 U.S. states
For-Profit Prisons: How Lobbying Has Affected the Way America Houses Prisoners
No full textThere seems to be limited research and understanding as to why for-profit prisons exist in the United States. The initial selling points used to sell private prisons to states and counties were that they would reduce recidivism and cost. Recent peer-reviewed studies have found, however, that neither are the case. This could lead one to ask why for-profit prisons are still used in America. That is what I hope to answer in this research paper. After research and analysis of campaign donations by the two largest for-profit prison corporations (collected from the National Institute on Money in State Politics) and changes in the population of prisoners held in for-profit facilities (collected from the Bureau of Justice Statistics), I found that the states that have seen an increase in the number of prisoners in for-profit facilities have a higher mean number of dollars donated to elected officials. This seems to indicate that decisions regarding incarceration may have more to do with campaign donations than justice
Effects of Rainbow Trout on Brook Trout Population Size in Tributaries to Lake Superior in Cook County, Minnesota
No full textThis study looked at the effects of Rainbow Trout stocking on the size of Brook Trout populations above migratory barriers. Linear mixed effects models were used to determine if there was a relationship between Brook Trout and Rainbow Trout catch rates. Age 1 or older Brook Trout populations were influenced by relative abundance of age 1 or older Rainbow Trout, according to the best supported model based on AIC scores. Population responses varied by stream, ranging along a gradient from high catch rates with a positive relationship to a negative relationship with low relative abundances. Streams with a positive relationship are likely more productive, with more prey and smaller territories, which allows for greater relative abundance. Streams with a weak relationship may have Brook Trout populations limited by the capacity for natural reproduction, a factor which would not influence Rainbow Trout. A clear negative relationship in some streams is likely due to density-dependent effects. This study did not perform an analysis comparing Brook Trout population sizes before and after the presence of Rainbow Trout. It is possible, but undetermined, that Brook Trout populations in this study would be larger if not for the introduction of Rainbow Trout. Management of Brook Trout and Rainbow Trout populations should be considered on a stream-by-stream basis due to the wide variation in population responses, and particular attention should be paid to the potential effects of Rainbow Trout introduction on streams with low abundances of Brook Trout
Body-worn Cameras and Officer Behavior
No full textThe use of body-worn cameras in law enforcement is controversial because there are possible disadvantages among the numerous advantages. Body-worn cameras are often implemented to reduce use of force by officers. A majority of studies on the effects of law enforcement using body-worn cameras found that the use of body-worn cameras reduced use of force as well as other aspects of officer behavior. Law enforcement officers using body-worn cameras are more likely to write citations, less likely to arrest, and will often report more self- initiated incidents. This may be because officers wearing body-worn cameras worry that the use of discretion on recorded incidents could lead to disciplinary action. Body-worn cameras are simply a new tool for law enforcement agencies and it will take time for them to become socialized within departments
Age-0 Walleye Growth Rates Following Spiny Water Flea Bythotrephes longimanus Invasion
No full textWithin Voyageurs National Park, spiny water flea Bythotrephes longimanus has reduced Lake Kabetogama and Rainy Lake native zooplankton biomass during summer peak by 40-60%. Subsequently, planktivorous age-0 Yellow Perch Perca flavescens growth has decreased. A possible trophic cascade may influence predatory fish growth rates like that of age-0 Walleye Sander vitreus. Using seine net and electrofishing data, age-0 Walleye growth rates were modeled as a linear function of growing degree days (GDD) and the slope was compared between pre- and post-spiny water flea establishment. Nearby Lake Vermilion, assumed to have been unaffected by spiny water flea until 2015 and found to have no changes in Yellow Perch growth, was used as a reference for natural variation in age-0 Walleye growth in the region. At 1050 GDD, the two infected lakes showed either no change (Lake Kabetogama) or a decline in mean growth rate (Rainy Lake) of 5% related to GDD, whereas the uninfected lake (Lake Vermilion) showed an increase in mean growth rate of 9% during the same time period. The effects spiny water fleas have on age-0 Walleye growth varied from lake to lake and its broader implications are not completely clear. A lakes limnological characteristics and management plans for Walleye may contribute to changes in growth rates of age-0 Walleye just as much as the presence of spiny water flea. Further monitoring and analysis of now infested Lake Vermilion (this studies refence lake) may help determine the effects spiny water fleas have on age-0 Walleye growth